1. Field of the Invention
The invention relates to a system for displaying and capturing images, and in particular to a system having a display mode, a touch mode, and a scan mode.
2. Description of the Related Art
With the rise of electronic commerce and the increased transmission rate of information exchange, conventional input interfaces, such as keyboards and mice, cannot adequately satisfy the requirement for rapid data transmission. Thus, new modes of inputting information, such as vocal and handwritten input, often replace conventional input interfaces. One example of an alternative input interface is the touch panel.
In conventional touch panels, because leakage current of amorphous silicon thin film transistors (a-Si TFTs) is sensitive to light, a-Si TFTs are employed to form photodiodes for using as image sensors. Jeong Hyun Kim of LG. Philips LCD Co. discloses a fingerprint scanner, in which a photodiode formed by an a-Si TFT senses the light reflected from a finger.